Comparative genetic organization of incompatibility group P degradative plasmids

Abstract

Plasmids that encode genes for the degradation of recalcitrant compounds are often examined only for characteristics of the degradative pathways and ignore regions that are necessary for plasmid replication, incompatibility, and conjugation. If these characteristics were known, then the mobility of the catabolic genes between species could be predicted and different catabolic pathways might be combined to alter substrate range. Two catabolic plasmids, pSS50 and pSS60, isolated from chlorobiphenyl-degrading strains and a 3-chlorobenzoate-degrading plasmid, pBR60, were compared with the previously described IncP group (Pseudomonas group P-i) plasmids pJP4 and R751. All three of the former plasmids were also members of the IncP group, although pBR60 is apparently more distantly related. DNA probes specific for known genetic loci were used to determine the order of homologous loci on the plasmids. In all of these plasmids the order is invariant, demonstrating the conservation of this "backbone" region. In addition, all five plasmids display at least some homology with the mercury resistance transposon, Tn501, which has been suggested to be characteristic of the 13 subgroup of the IncP plasmids. Plasmids pSS50 and pSS60 have been mapped in detail, and repeat sequences that surround the suspected degradation genes are described.

Complete Nucleotide Sequence and Organization of the Atrazine Catabolic Plasmid pADP-1 from Pseudomonas sp . Strain ADP

“…2). Members of the IncP plasmid group have been shown to be highly conserved despite the fact that they have been isolated from diverse genera of bacteria in different parts of the world (11,54,60). Antibiotic resistance, mercury resistance, and other catabolic genes have previously been identified on diverse IncP plasmids (11,54).…”

“…The latter group of plasmids consist predominantly of those known to contain antibiotic resistance genes or encode virulence determinants associated with infectious diseases (5,29,52). In contrast, catabolic plasmids, which have been identified in many nonpathogenic soil bacteria (49), have been shown to transfer among bacteria, thus disseminating genes encoding the metabolism of environmentally relevant compounds (11). For example, plasmids encoding the catabolism of toluene, camphor, naphthalene, and 2,4-dichlorophenoxyacetate are known (3,12,45,64).…”

Isolation and molecular characterization of some copper biosorped strains

“…The toxicity assay was performed using a bioluminescent bioreporter Acinetobacter strain DF4/ PUTK2 that had been genetically modified by conjugation (Abd-El-Haleem et al, 2006) to contain the PUTK2 plasmid (Burlage et al, 1990), with the Tn4431 lux transposon downstream of a putative plasmid maintenance promoter to produce continual visible bioluminescence light. Bioluminescence was measured at 5 min regular time intervals from zero to 480 min by a luminometer (LumiStar, Galaxy, BMG, Germany).…”

Molecular Ecology of Bacterial Populations in Environmental Hazardous Chemical Control

“…Initial digests of pSS60 with Sph I indicated that it was 10 kb larger than pSS50 (3,22). The restriction map of pSS60 is very similar to pSS50 excepting that it has a unique 7kb region which does not hybridize to pSS50 ( Figure 6).…”